Air-compressor



(No Model.)

I'. H. RICHARDS. AIR COMPRESSOR.

No. 462,776. Patented Nov. 10,1891.

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UNITED STATES PATENT OEEIcE.

'FRANCIS H. RICHARDS, OF HARTFORD, CONNECTICUT, ASSIGNOR TO ECKLEY ll. COKE, OF DRIFTON, PENNSYLVANIA.

AIR-COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 462,776, dated November lO, 1891.

Application filed April 2l, 1891. Serial No. 389,786. (No model.)

T0 all whom t may] concern:

Be it known that I, FRANCIS H. RICHARDS. a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Air-Compressors, of which the following is a specication.

This invention relates to air-compressors of the class having the so-ealled luid-piston,7 the object of the invention being to furnish means for better economizing power by effectually cooling the air simultaneously with the compression thereof.

In the drawings accompanying and forming a part 'of this specification, Figure l is an end elevation of so much of an air-compressor as embodies my present invention. Fig. 2 is a vertical longitudinal section of the machine. Fig. 3 is an enlarged top view of a portion of the compression-cylinder, showing a preferred arrangement of the aircooling means. Fig. 4 is an enlarged vertical sectional view similar to a portion of Fig. 3, showing in detail the preferred mode of supporting the vertical cooling-plates shown in plan view in Fig. 3. Fig. 5 is a view similar to a portion of Fig. 3, showing one modified arrangement of the heat-abstractiug plates. Fig. 6 is another similar view illustrating another modication of the heat-abstracters.

Similar characters designate like parts in all the figures. 4

It will be remembered that in the compressing of air heat is produced thereby, aportion of the latent heat of the air being converted into sensible heat by the change of volume due to the compression. This heating of the air, as is Well known, results in practice in a considerable loss of power, since the heating of the air normally expands it to alarger volume. To overcome this diiiiculty the expe` dient has been resorted to of using water in the cylinders of the compressors, and also of using water-jacketed cylinders. These means, however, operate very inefticiently, since the air, being in a considerable volume and a slow conductor of heat,"naturally retains its heat for a relatively long period, this being Ineasnred, of course, by the duration of the act of compression.

According to my present improvements, I use the so-called fluid-pistou, and in connection therewith employ meansfor abstracting the heat from the interior spaces of the volume of air under compression. These means consistof suitable heat-abstracters interspersed throughout the interior space of the compresser-chamber. The operation of these heat-abstracters is to receive heat of compression from the air during the act of compression and afterward to give olf that heat to the water or other iiuid constituting the Huid-piston. Said heat-abstracters, being interspersed as described and standing iu close proximity to each other, act throughout the unsubmerged portion thereof to receive the heat of compression from the air instantly the heat is formed, thereby a voiding a further expenditure of power to overcome the aforesaid normal increase in the volume of the air being compressed.

The compressor consists ot' the usual watercylinder C, in which the plunger P (to be operated in the usual manner by some plungeractuating mechanism not shown) is iitted to slide through the usual packing 2 and gland 3. The proper stroke of the plunger P is indicated in Fig. 2 by the dotted lines P. The water-cylinder is or may be supported by a frame or bed -plate B, and is constructed for receiving on the upper side thereof the compression-chamber D, which may be held in place -by the usual bolts 4, passing through the lower flange 5 of said chamber and into the upper flange 6 of said cylinder. On its upper end the compressiou-chamber carries the cap or plate E, which is or may be removably fixed to the compression-charnber by` suitable bolts, as 7, in a well-known manner. The top plate or cap E carries the inlet and outlet valves F and G, respectively. The inlet-valve F is or may be carried on the lower end of the valve-stein S, and is lifted by a spring 9 on said steln above the spider l0, that is' removably fixed in place by means of the threaded hollow stem of the screen S. As shown in the drawings, the valve-seat l2 for said inlet-valve F is formed in a removable hollow plug 13. This arrangement permits the use of diierent materials for the respect- IOO chamber.

ive parts, and also permits the convenient removal of the valve and its seat by nnscrewing the plug 13. The outlet-valve Gis shown fitted to a valve-seat formed in the plate E, and has it stem 17 guided at. the upper end thereof in the removable nut or cap 14, which is screwed into the valve-chamber 15, formed on the aforesaid top plate E. A spring 16 on said stein 17 serves to return the valve to its seat when it has been' lifted. The deliverypipe 18 conducts the air away from the valvechamber.

The heat-abstracters consist in their preferred form of metallic plates suitably supported in close proximity to each other and interspersed throughout the interior of the compression-chamber. The construction and arrangement of the plates which are deemed most effective and economical are shown in Fig. 3, the plates being arranged in sets, and each set consisting of aseries of double plates joined at their outer edges by a connectingplate, furnishing a means of properly holding the plates in position within the compression- In Fig. 3 the sets of platesA A A are of the saine proportions and construction, While the sets of plates B and B are relatively narrower; but otherwise of the same construction. rlhe obj ect of said variation is to better subdivide the cross-sectional area of the compressor-chamberinto narrow areas. The set of cooling-plates shown consists of the plates a a b b c c CZ cl,of decreasing widths,substan tially as shown. The plates d a are connected at their outer edges by the plate a, the plates b b by the plate b, the plates c c by the plate c, and the plates d d by the plate c The several pairs of plates in the same set have these connecting-plates superimposed one upon the other, as indicated in the drawings, these being connected together by suitable rivets, as 20, which pass through said connecting-plates d h c d and. through the flanges 22 and 24 of the plate-carrier 25, as best shown in Figs. 3 and 4. As shown in Fig. 3, the two plates of each pair of plates are parallel with each other, the plates being in this form most easily constructed.

In operating the compressor the cylinder C is filled with water or other suitable fiuid, (oil being sometimes employed for this purpose,) the Water reaching, when the plunger is withdrawn, to its outermost position (shown by solid lines in Fig. 2) to about the height of the line L, and when the plunger is at,the opposite end of its stroke (shown by the dotted lines P) rising to the height of the line N within the valve-chamber 15. As the fluid rises Within the compressor-cliamber, the air is compressed and heat generated, which-is immediately absorbed by the submerged portions of the abstracters or plates. At the same time these plates, being good conductors of heat and being partially immersed in the rising iiuid, rapidly conduct the heat downward into and impart the same to the fiuid. By this means heat is instantly and rapidly abstracted from the air and transmitted to the Huid-piston, which in practice should be oversupplied at each stroke by the .usual supply-pump, (not shown,) which is suitably connected with the cylinder C by means of the pipe K. .The oversupply of fluid is discharged at the termination of each stroke by the plunger P through the outlet-valve G and the discharge-pipe 1S. By means of this constant replenishing of the fluid of the huid-piston the mass of fiuid within the compressor is kept relatively cool. At each stroke the heatabstracting plates are entirely immersed in the fluid, Vand, thereby thoroughly cooled, ready for effective operation at the next stroke of the compressor. The plates, being continuous solid metal to a point b elow the water-line, act during the compression to receive the heat and rapidly conduct the saine downward and discharge it into the fluidpiston, thereby materially reducing the heating of the upper portions of the plates, and thus maintaining those portions in the in ost effective condition. During the compression the plates are being continuously submerged (throughout their entire cross-sectional periphery) from the lower end upwardly.

The plates or other forms of heat-abstracters, whereby the compression-chamber is subdivided into narrow spaces, being immersed at each stroke of the plunger in the fluidpiston are on the descent of the piston covered with a thin coating or layer of water, (or other like fiuid nsed,) which promotes the action of the plates 'for cooling the air being compressed.

The particular construction andY arrangement of the heat-abstracters are not limited to the particular construction and arrangement of the heat-abstracting plates, nor to the use of the heat-abstracters in the form of plates. In Fig. 5 the said abstracter-plate is shown in plan View in a serpentine form, (designated by 30, and occupying the space of one of the'sets of plates, as A or B, Fig. 3.) In Fig. 6 the heatabstractor consists of a series-of wires or tubes, as 40, set vertically and in close proximity to each other.

Having thus described my invention, I 'claim- 1. In an air-compi'essor, the' combination,

IOO

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'IISY with a compression-chamber having an inletcated within said chamber and dividing the t interior thereof into narrow spaces, and the rising and falling fluid-piston partially submerging said plates when in its lowest position and fully submerging the same when in its uppermost position, substantially as described.

3. In an air-con'ipressor, the combination, with a compression-chamber, substantially as described, of a set of heat-abstracting plates, consisting of pairs of connected plates superimposed one upon the other and projecting into the interior of said chamber, substantially as described.

4C. In an air-compressor, the combination, with the Water-cylinder and with the compression-chamber located above the Water-cylinder, of the plate-carrier supported at the lower end of said chamber and carrying heatabstracting plates extending upwardly into the interior of said chamber, substantially as described.

5. In an air-compressor, the combination, with the pump-cylinder C, constructed to support the compressioli-chamber, of the vertical compression-chamber supported on the pumpcylinder, the plate-carrier having a flange intermediate to the pump-cylinder 'and compression-chamber, and a series of plates fixed to the inner side of said carrier and extending inwardly and upwardly therefrom into the interior of the compression-chamber, substantially as described.

(i. In an air-compressor, the combination, with the cylindrical compressionchamber thereof, of a removable plate-carrier, substantially as described, and a series of heatabstracting plates fixed Within said carrier and having the plates of cach set of successively decreasing Widths from the middle of the set outward, substantially as described.

7. In an air-compressor having a compression-chamber, substantially as described, the combination, with the plate-carrier having a fiange in said chamber, of the series of superimposed plates rigidly attached to said ange, substantially as set forth.

FRANCIS II. RICHARDS.

Witnesses:

HENRY L. RECKARD, II. MALLNER. 

